Manzella, Johnson and Sadler, 27, will join the club today for the start of a three-game series against the Braves at Minute Maid Park.

“This is a situation for them to come and learn and learn from some of the best players who ever played, particularly in this town,” Cecil Cooper said.

Manzella, 26, and Johnson, 24, have never been in the majors. Sadler was signed this summer with the condition that he get a promotion to the majors if healthy. They join catcher J.R. Towles, who arrived Friday, as the only players added to the roster this month other than those who were activated from the disabled list Sept. 1.

Johnson, the Express' offensive player of the month in August, hit .281 with 13 home runs and 20 doubles with 42 RBIs while being limited to 104 games because of injury. Cooper lobbied general manager Ed Wade to promote Johnson, who could be the club's third baseman next season.

Manzella, who is considered the Astros' shortstop of the future, hit .289 with nine home runs and 56 RBIs. Sadler signed with the Astros after he was released by the San Francisco Giants. The call-ups likely will take some starts from Miguel Tejada, Geoff Blum and Aaron Boone.

“It won't be a lot, but they will get a chance to play,” Cooper said. “The fans will get a chance to see them.”